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Caltech Scientists Film Photons With Electrons
al0ha writes "Techniques recently invented by researchers at the California Institute of Technology which allow the real-time, real-space visualization of fleeting changes in the structure of nanoscale matter have been used to image the evanescent electrical fields produced by the interaction of electrons and photons, and to track changes in atomic-scale structures."
This is actually quite applicable to quantum computing. We are getting to the point where we can define the qubits, but have trouble measuring the photon emissions that indicate the result of the computation. This will allow us to finally measure what amounts to the result of the quantum calculation. It's been a long time in coming, but this will finally allow us to make some significant strides towards commercializing quantum computing.
I didn't see that coming.
(C'mon! It's funny! Photons! Femtoseconds! Ahh.. fergetaboutit.)
Am I just not looking hard enough?
Try squinting. It's all so very small scale.
Learning about brewing beer, by brewing beer.
It's Friday, I'm drunk, but what the FUCK?! I can't grasp..
Fuck. CalTech. Guess them nerds do know what they're doing.
I met nerds from CalTech and MIT. MIT nerds got nothing on CalTech nerds. When it comes to physics, I'd go with CalTech nerds. p. The nerd from my Ivy League school just don't measure up, including me...
Fuck systemd. Fuck Redhat. Fuck Soylent, too. Wait, scratch the last one.
The photo-electric effect is when electrons are released from a material when they absorb energy from photons. When the energy of the photons isn't above the threshold energy of the material, you get nothing. Also the energy of the emitted electrons doesn't depend on the intensity of the light.
This new technique called PINEM (photon-induced near-field electron microscopy), is used to image the "glow" (i.e., photon emissions) that is emitted by objects that have been excited by femto-second laser pulses using short pulses of electron beams. The image of the object glow is formed by measuring the energy of the scatterred short electron beam.
So in PINEM we are measuring a photons field using an electron pulse in a way where the electrons have a scatter function and different electron energies (think of this as an "analog" 4-d picture of the photon field), in the PE-effect, we are getting some number of electrons of a fixed energy which we can count (think of this like a "geiger counter" measurement of the incident photon field on the material).
Also since you are measuring a field and not the material, in the PE-effect, the material has to absorb the photon and emit (non-coherently) at it's electron work function energy. If the absorbtion ability and/or the energy disparity beween the photons and the work function is large, PE-effect doesn't even give you anything.
As a not very good analogy to think about, with PINEM, you can effectively take a "flash" picture (the flash is the femto-second laser pulse) of the photon emmission field which doesn't disturb the material that much. With any imaging technique that tried to use the PE effect, you'd have to illumiate the material with a photon field (over time and with different intensities) which wouldn't allow you to see anything. This would be like taking a picture with no shutter over a long period of time and imaging them with a binary threshold (kinda-like how old fax machines scanned pictures before dithering). Very blurry (because of the time averaging of the illumiation to get electrons emitted), and very uninteresting (because of the single energy level, uncorrelated nature of the electron emmission from the PE-effect). As another silly analogy, PE-effect is like hearing the alarm of water going above a dam, where PINEM is like looking at the a 3-d movie of the water-level behind the dam even if the water level didn't go above the dam.
Saying this is "old news" is like saying that the transistor was old news, because we discovered lightning a long time ago. ;^)